Air operated chuck



Feb. 2, 1960 J o GARRlSON 1 AL 2,923,554

AIR OPERATED CHUCK Filed Feb. 3, 1958 INV EN TOR5 (ll/75S Giff/S 011/ BY 6mm AIR OPERATED CHUCK dames O.-Garrison and David D. Walker, Dayton, Ohio, assignors to Garrison Machine Works, Inc., Dayton, Ohio, a corporation of Ohio Application February 3, 1958, Serial No. 712,941

Claims. (c1. 279-4 This invention relates to chucks utilizing a plurality of jaws movable in unison to grip and release a work piece, and more particularly to fluid pressure operated devices of the kind described in which motion of the chuck fjaws in'at least one direction is efiected by fluid pressure 1 lunder remote control.

The object of the invention is to simplify the construcition as well as the means and mode of operation of fluid operated chucks, whereby such chucks may not only due economically manufactured, but will be more efficient :and satisfactory in use, adaptable to a wide variety of applications, and be unlikely to get out of order.

A further object of-the invention is to introduce a ways are comprised in and made an integral part of the chuck structure. 4

A further object of the invention is to utilize a tubular bushing as a mount for the chuck jaw and as a means to conduct fluid for the operation of the jaw, and in conjunc tion therewith to provide simple and effective means for sealing against the loss of pressure fluid from the system.

A further object of the invention is to provide a fluid operated chuck possessing the advantageous structural features, the inherent meritorious characteristics and the mode of operation herein mentioned.

With the above and other incidental objects in view as will more fully appear in the specification, the invention intended to'be protected by Letters Patent consists of the features of construction, the parts and combinations thereof, and the mode of operation as hereinafter described or illustrated in the accompanying drawings, or their equiva i lents.

Referring to the accompanying drawing wherein is shown one but obviously not necessarily the only form of embodiment of the invention,

Fig. 1 is a view in longitudinal section of a chuck in- 'accordance with theillustratcd embodiment of the invention, only one chuck jaw being shown and a work piece to be gripped being indicated in dot-dash outline;

Fig. 2 is a fragmentary view in front elevation of the chuck of Fig. 1, a part of the chuck jaw being broken away to show the fluid pressure operated device therein and the pivot stud and associated parts upon which the chuck jaw is mounted being omitted;

Fig. 3 is a view like Fig. 2, but completely in elevation and with all parts included; and

Fig. 4 is a detail view of a spring device cooperating with the fluid pressure device to effect and control the movements of the chuck jaw, being a sectional view taken substantially along the line 44 of Fig. 2,

' 2,923,554 Patented l i'eb. 2,

Like parts are indicated bysimilar characters of reference throughout the 'several views.

Referringto the drawing, .he invention is disclosed as embodied in a gear chuck comprising a body 10 having a circular. series of longitudinal through openings 11' by which. the chuck body can be bolted or otherwise secured to a stationary support. On whatmay be considered to be the upper. or outer sideof the body It! is a planar surface 12 in the approximate center of WhlCh'IS a recess 13. Projecting into the reces s 13, fromthe bottom thereof, is a circular, series ofpins 14 constituting rests or supports for a gear blank 15." In surrounding relation to the recess 13, andsupported on the body 10 in a manner later to be considered, is a circular series of chuck jaws16 (one shown) movable in an oscillatory manner inja plane parallel to thesurface 12 to grip and to. release the blank 15.? As indicated, the work engaging portions of the chuck jaws 16 are formed with teeth 17 adapted to engage teeth on'the gear blank for a secure holding thereof to permit-precision grinding, facing and like operations to be performed thereon.

The instant invention is more particularly' concerned with the construction, mounting'and mode-of operation of the chuck jaws, and since all of these are the same for each of the jaws, only onev is disclosed herein Opening into the body 10, from the under side'thereof, isa bore 18 which is an air inlet common to -the severalfchuck jaws, the bore being adapted to be permanently connected to a pressure fluid conducting pipe line or the like which incorporates at a realtively remote point a valve or other means by which the fluid under. pressuremay selectively be communicated to the inlet 18.

Extending from the inlet 18 .to each chuck jaw is a supply passage 19 which isin intersecting relation toa bore 21 opening through'the. surface 12; Installed in the bore 21 is one.end ofaitubularbushing 22, the other end of which projects through and beyond the surface 12. The installed or inner end of the bushing 22 is anchored in the body 10 by a screw .23 having accessto the bore 21 from the under side of the body by way of an opening 24. The screw 23v has a threaded engagement in the vadjacentopen end of the bushing 22and serves both as ananchor for the bushing and as a means to close one endof the interior of the bushing. The other end thereof is closed by the threaded shank of a similar screw 25 sage or chamber 26 with the supply duct 19 in'the body. Another set of radial ports' 28 in the bushing 22 com-, 7

municate the interior passage 26 with an annular groove 29 therein. The latter in turn communicates withv one end of a fluid passage 31 in a chuck jaw 16, which jaw is mounted on the projectingend of the bushing 22 for relative swinging motion, the bushing sewing as a. pivot stud for the chuck jaw. V V

The passage 31 extends forwardly in the chuck jaw and communicates Withthe inner end of a piston chamber 32 opening through one side edge ofthe jaw. Slide ably mounted in thechamber '32 ,is a piston 33 on the inner endof which is ajreversely disposedcup seal 34. The construction and arrangement of parts, it willbe understood, is such that the admission of fluid'under pressure to the chamber 32 tends to effect a relativefexa reactant member inrcspouse to the. energizing ofvthg chamber. interior 32 with pressure fluid, whereby. the motion tending to extend the piston 33 is resolved instead, into a leftward (Fig: 2) movement of the chuck' aw: itselfwhile the": pjston33.'t. remains 'stationari11y.: cn-

"gaged with the reactantimeinhen stud 35'. ;-Beinglme nted the jaw is effective to movethe toothed portion117 .thereoffnotlonly'inqa' lateral sensebut-also inzafradia'l rela tive approaching sense with-respect to the periphery of work piece l-s wher'eby the'cooperative actionzof the sev.- erai chuck jaws engaging ditferent portions of the =periph= eryof thework piecer'nay result in the piece being-firm- 1y clamped and held by the jaws. v

Motion ofthechuck jaw in anopposite' or clock-wise 5-. d

' gripping and releasing posltrous, arelatively stationary sa d jawmember, 'meansnto supply pressure. fluid topsa id chamber, P st n (re i d i sai ham n F ses" direction ofmovement, as indicated in Fig; 2, is effected bye torsion spring36 which surroundsa spacer element QZ-lQcated'betWeen the chuck jaw'and'th'e surfaceil zt of the body. The spring 36 is-in efiect a split rin'g, with one end thereofanchored;as' shown in Fig. 4; in a recess=37 in the-body 10-and withthe other end thereof similarly anchoredin-a recess 38"in the jaw 16. Motion ba he chuck jaw'und'er-the influence of applied pressure fluid s'ervesto wind or to-tension the spring 36 so that moineffect loads or tensions the'spring. Upon release ot theapplied air pressure, the chuck jaw is restored to con:-

trolof-Ethe' spring 36 which returns, it in a clock-wise dire c- -tion' of the chuck jaw in a directionto grip the work r's iii.

posse si the par iqu a .f a u of a nta b or enumerated as desirable, hint which obviously is' as: ceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages. V

While in order to comply'with the statute the invenvention has been-'deseribed'in langnage rnore or less specific as to structural features, it is to be understood that theginventiongisnot limited'to' the specific features shown; but that the means and construction herein disclosed comprise but one of severalmodes-of"putting the invenliOHj iHiOwCfi CCt; and, thelinyent-ion is. therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

Having'thus described our invention, we claim:

1. A chuck, including a body, at least one work enn jaw emb 011 t a 20d!- m v b haw??? WW reactant means: on .said body, a piston chamber 1 ing said reactantmeans, the supply Q -PI ESSWQ ttQ s hamb sult n i -mq m nt o s aw; ms=

q per gwi iaw imhewrk sl ppin mq ttba thereof. 17 r t tion asgviewed in FigJZLto a position o f release with respect to the work-piece. .The chuck jaw thus is-movable between, work gripping andwork'releasing positions; in 'the' one'instance by fluid pressure and inthe "of the jaw in the firstinstance, v

otherinstanceby' spring means tensioned bymovement M ;opening39 in the jaw lti," through which opening extends jthe bushing 22. "The passage registers with the; annul r vc Q1 t us To bi n s a e o stalled between such periphery and the surface. 16; The

result is substantially to preclude the escape of pressure ;2,-. Achu k ac ordingtoacla im ch twtet l ti vthattsaid an -t m vesa di w mem e i 3. A chu k in lud ng. r a: beds/ 2 l tfleast tone workmen: e sing j w: nsa d hodyi rabl betwe n wo :ensa's- I ing and releasing positions a relativelyetationary Q ;;actant :-means-- onzjsaid .hody, a:piston-;chamber in said. jaw, a piston havingone end received in Saidchamber andgthe; other end-extending therefrom .toward contact fluidf from the opening 39 outward over the uppersurthe' cap 42 in an assembled position, upon the "jaw 16 fsqueeze' or compression to: the seal 43" upon the surthe-admissionof fluid'under pressure to the inlet 18 pressure-is applied at substantially thesame momen't'to all of the chambers 32 with the result that allof the jaws "11'6 jmove' simultaneously to. grip the. work. Each jaw,

alternately-top source: of pressure .fluidnand to exhaust, .the pressure in eaeh of the. chambers 32 isjreleased and the; severaljawshareafree .to return to released .position l nder,.the urging.ofltheir respective springs; 36.

.Erfomgthe ,above descriptionjt willbe apparent that *th'ere is'=-thus "providd a device'ofth' character described is" adjusted to apply a predetermined amount of a ra e of the jawf16. The cap screw .25 serves to hold It will be understood that the chamberi32 of each jaw N 1 6 is continuously. open to'the air inlet 18 andthat upon 1yvithwsaid,reactant means yieldinglmeans urging s'aidtjayv.

in'a direction to engage said;pist on..with said reactant means, means including a pressure .fluid, passage leading through s d ja o t dchamb r o s pp y u dunde pre ur t sa d; ha ber to. mor said; la a ain t-t urgi g" f. id ty eldingeem ansand la v y to. ai p n amt-ethe w rk e a n :vmeans'q aid b0 cooperating the e 'from said body, work holding means including a: chuck jaw'rotatable gn-saidpivot stud, a. piston chamber-in aid jaw, a pistonhaving one end received insaidgchamber, relatively, stationary, reactant means on said body; engageable by the other end of said piston, and a pressure fluld ;-passage way extendingfrorn said body. through isaid p ivot stud audt'throughsaidjawtq supply fiuidunder pressure to said piston chamber toetfect a.;relative s epa r ating;m9-

a chuck jaw pivotally rnounted on said stud, ya piston chamber in said ch uckjaw, a piston in saidchambenre 1 actant means onsaid body engageable-by said piston,

.and a pressure fluid conductingpassage in.said .jawcommunicating said, piston chamber. with; the, longitudinally xten ra sas sai -R v t st d j 6. A chuck, including ,a body having, a pressure fluid conducting passage, a. tuh'ular bushing. having 1. one end 1 received in said' hody in inter secting g relation to said passage and having its other end"projctin"g from said yielding a means t ns ons-d y mo em nt, of sa a. v. t 1

.dr 7 with aidria rin he wor ens s spqsrt pu A h c ..iuQ1udin.-- y.a r vet rroiss ire body, work holding means including a chuck jaw pivotally mounted on the projecting end of said bushing, lateral openings in said bushings to communicate the interior thereof with the said fluid passage in said body, means to close the projecting end of said bushing against the escape of pressure fluid there from, a fluid conducting passage in said jaw, openings in said bushing to communicate the interior thereof with said last named passage, and a fluid pressure operated device carried by said jaw and reacting against said body to move said jaw in response to the supply of pressure fluid to said device by said last named passage.

7. A chuck including a body having a pressure fluid supply passage therein, a recess insaid body intersecting said supply passage, a tubular bushing having one end received in said recess and the other end projecting therefrom, the interior of said bushing communicating with said supply passage, work holding means including a chuck jaw having a through opening through which the projecting end of said bushing extends, said jaw being thereby pivotally mounted on said bushing, a cap assembly seated on said chuck jaw in concentric relation to said bushing and including sealing means to inhibit escape of pressure fluid outwardly of the opening in said jaw, said assembly further including screw means re ceived in the projecting end of said bushing, a pressure fluid operated device carried by said chuck jaw and reacting against said body to rock said jaw about said bushing in response to a supply of pressure fluid thereto, and a fluid conducting passage from the interior. of said bushing through said jaw to said device therein.

8. A chuck, according to claim 7, characterized by spring means urging said jaw in one direction, said pressure fluid operated device being arranged to move said jaw in the opposite direction.

9. A chuck including a body, at least one work engaging jaw member mounted on said body for rocking motion between work gripping and releasing positions, fluid pressure operated means to move said jaw to one of said positions and to control its movement to the other position, said means including a piston interposed between said body and said jaw and ducts to introduce pressure fluid between said piston and said jaw, the introduction of such pressure efiecting a relative separating motion of said jaw from said piston toward said one position, and yielding means tensioned by movement of said jaw to said one position to return it to said other position upon release of applied fluid pressure between said jaw and said piston, and other work engaging means on said body cooperating with said jaw in the work gripping position thereof.

10. A chuck, including a body, a plurality of work engaging jaw members on said body movable between work gripping and releasing positions, relatively stationary reactant means on said body individual to each of said jaw members, a piston chamber in each of said jaw members, a piston received in said chamber and engaging a respective reactant means, a supply of pressure fluid to said chamber resulting in a movement of said jaw member relatively to said piston to one of said positions, means to move said jaw members to the other one of said positions, and means to supply pressure fluid simultaneously to the chambers of all of said jaw members and simultaneously to discontinue such supply.

References Cited in the file of this patent UNITED STATES PATENTS 1,815,562 Godfriaux July 21, 1931 2,323,091 Johnston et a1. June 29, 1943 2,587,893 Pridy et a1. Mar. 4, 1952 2,667,356 Forward Jan. 26, 1954 2,747,882 Garrison et a1. May 29, 1956 2,785,904 Garrison et al Mar. 19, 1957 

